Winter 2023/24
W inter 2023 / 2024 was the warmest in 130 years of recordkeeping. We had ample rainfall right into the spring and very early summer, but right now we are on the dry side. With the extreme heat waves we have been experiencing in July, trees and shrubs are looking a bit stressed, so try to be diligent about watering. 2023 was a good recovery year with excessive rainfall after the severe drought of 2022. Supplemental watering right now is very important for trees planted in the past two years and for trees that have not fully recovered from the drought of 2022.
Drought conditions cause stress to trees, making them more susceptible to many insects and diseases, with symptoms not showing up for one to two years. I am seeing wood-boring insects that I have never seen in my 47 years of tree care, such as the ambrosia beetle. This insect is opportunistic and preys on susceptible host trees that have been weakened by drought.
I am seeing bagworms on Emerald arborvitae this summer that were planted two years ago. I have seen bagworms a few times on evergreens shipped out of southern farms from North Carolina up into Maryland, but have never worried much about them because our first frost here in New England typically kills them. Southern insects shipped on Nursery stock surviving this past record-warm winter is one of the first times that I have experienced the ill effects on trees caused by global warming.
Perhaps the most positive side effect of last winter’s extreme warmth is the exceptional splash of blue flowers on Macrophylla hydrangea varieties, most notably ‘Nikko Blue’. Macrophylla varieties are not consistent bloomers in our area because the flowers bloom on last year‘s wood, which is most often burnt by frost. These varieties are reliable bloomers on Cape Cod and some areas east of 128 because the winter conditions are milder.
I have fielded hundreds of calls over the years asking: “Why do my hydrangeas produce lush foliage and no flowers?”. The simple answer is they just don’t belong here; they belong in areas with milder winters. Personally, I think the blue flowers are pretty, but at the same time, I see nature’s clock confused, which concerns me. For example, Hydrangeas and Rose of Sharon have always flowered late summer starting in mid-August, not mid-July as they did this summer. Hydrangea paniculata varieties such as PeeGee, Limelight, and PinkyWinky, on the other hand, are consistent bloomers in this area and can withstand temperatures as low as zone 3.
We were zone 5 and I understand that we are now a zone 6B, but most concerning to me is that amid our average warmer temperatures, we will have short periods of extremely below-average temperatures. It only takes 24 hours of extreme cold to cause winter burn, so the future should be interesting.
If you see something unusual with your trees and shrubs, please call and let’s talk about it so we can learn from each other. It takes keen observation and the sharing of information in the fascinating realm of nature to understand these differences. Accurate diagnostics will be the key to learning how we can adapt to our changing climate and integrate solutions into planning future landscapes.
Matthew R. Foti Landscape Design & Construction is a full service landscape design and construction firm. Established in 1977, Foti has maintained a 47 year commitment to high quality workmanship and personalized customer service. As a long time educator of aspiring Arborists and Horticulturalists, Matt’s small construction crew employs the most up to date planting and transplanting methods that will ensure the health and longevity of your landscape. Our continued education in a constantly changing industry combined with state of the art equipment has made Foti one of the leaders in the field. Contact Matt at 781-862-1010 .